IPv4 and IPv6 - CompTIA A+ 220-1101 - 2.5

Summary

The video script explains the fundamentals of Internet Protocol (IP) addressing, focusing on IPv4 and IPv6. It clarifies that IPv4, with its 32-bit structure, is running out of unique addresses, leading to the creation of IPv6, which offers a vast 128-bit address space. The script also covers the importance of subnet masks, default gateways, and DNS servers in network communication, emphasizing the transition from manual IP address memorization to using domain names for ease of access.

Takeaways

• 🌐 IPv4 is the primary internet protocol for device communication, with IP addresses used to identify devices on the network.
• 🔄 Most modern operating systems support both IPv4 and the newer IPv6, which offers a larger address space.
• 📍 An IPv4 address consists of four numbers separated by periods, each representing an 8-bit segment, totaling 32 bits.
• 📊 IPv4 addresses are limited to a maximum value of 255 per segment, which led to the development of IPv6 due to address exhaustion concerns.
• 🚀 IPv6 addresses are 128 bits long, providing a vast number of possible addresses, enough for every person on Earth to have many.
• 🔢 IPv6 addresses are divided into eight groups of 16 bits each, typically represented in hexadecimal format for easier handling.
• 🧩 IPv6 simplifies network addressing by using a 64-bit subnet mask, separating network and host addresses.
• 🛠️ Assigning an IP address to a device requires specifying the IP address, subnet mask, and default gateway for proper network communication.
• 🌐 The Domain Name System (DNS) is crucial for translating human-readable domain names into IP addresses for network routing.
• 🔀 Multiple DNS servers can be configured for redundancy, ensuring network reliability if one server is unavailable.
• 🔑 Configuring DNS in the operating system settings is common practice, with Google's 8.8.8.8 and 8.8.4.4 being popular choices.

Q & A

What is IPv4, and why is it important in today's networks?

IPv4, or Internet Protocol version 4, is the primary protocol used for most network communications today. It assigns unique IP addresses to devices, enabling them to communicate over a network.

How do IPv4 addresses differ from IPv6 addresses?

IPv4 addresses are 32-bit addresses represented as four decimal numbers separated by periods (e.g., 192.168.1.131). In contrast, IPv6 addresses are 128-bit addresses represented in hexadecimal format, separated into eight groups.

Why was IPv6 introduced, and what are its advantages over IPv4?

IPv6 was introduced due to the limited number of available IPv4 addresses. IPv6 provides a vastly larger address space, allowing for a greater number of devices to have unique IP addresses.

What is a subnet mask, and why is it needed?

A subnet mask is used to determine which portion of an IP address identifies the network and which part identifies the host. It is essential for organizing and routing traffic within a network.

What is the purpose of a default gateway in a network configuration?

A default gateway is the IP address of a router that allows devices on a local network to communicate with devices on other networks, such as the internet.

How is an IPv4 address structured in binary form?

An IPv4 address is structured as four 8-bit segments, each representing a decimal number between 0 and 255. For example, 192 in decimal is 11000000 in binary.

What role does DNS play in network communication?

DNS, or Domain Name System, translates domain names (like www.google.com) into IP addresses, making it easier for users to access websites without remembering numeric IP addresses.

Why might a device have multiple DNS servers configured?

Multiple DNS servers are configured as a redundancy measure. If one DNS server is unavailable, the device can use the secondary DNS server to resolve domain names.

What is the significance of the 64-bit subnet mask in IPv6?

In IPv6, a 64-bit subnet mask divides the address into a 64-bit network prefix and a 64-bit host identifier, which is common in most IPv6 network configurations.

Why is it important to avoid duplicate IP addresses in a network?

Duplicate IP addresses in a network can cause conflicts, leading to communication issues as devices might not be able to properly send or receive data if they share the same IP address.

Outlines

00:00

🌐 Understanding IPv4 and IPv6 Protocols

The script introduces the Internet Protocol (IP), specifically IPv4 and IPv6. IPv4 is the current standard with its addresses represented in four decimal numbers separated by periods, such as 192.168.1.131. It's explained that each number is an 8-bit segment, totaling 32 bits for the entire address. The limitations of IPv4 due to the rapid growth of the internet led to the creation of IPv6, which boasts a 128-bit address length, allowing for an astronomical number of unique addresses. IPv6 addresses are presented in groups of four hexadecimal digits separated by colons. The script also touches on the importance of DNS for simplifying the process of referring to servers by name rather than their complex IPv6 addresses.

05:00

🛠️ Configuring IP Addresses and DNS

This paragraph delves into the configuration of IP addresses, emphasizing the necessity of assigning unique IP addresses to each device on a network to avoid duplication. It explains the role of subnet masks in defining the network and host portions of an IP address, with a common example being 255.255.255.0. The paragraph further discusses the assignment of a default gateway, which is the IP address of a router that enables communication beyond the local subnet, using 192.168.1.1 as an example. The importance of the Domain Name System (DNS) is highlighted, as it translates human-readable domain names into IP addresses, facilitating easier navigation on the internet. The script mentions the configuration of DNS servers, such as Google's 8.8.8.8 and 8.8.4.4, as a critical component of network settings, often with backup DNS servers in place for reliability.

Keywords

💡IPv4

IPv4, or Internet Protocol version 4, is the fourth version of the Internet Protocol used for the identification and location of devices on a network. It is foundational to the way devices communicate over the internet. In the video, IPv4 is described as the primary protocol for network communication, with IP addresses being essential for devices to communicate with each other. An example of an IPv4 address provided in the script is 192.168.1.131, which is made up of four numbers separated by periods, each representing an 8-bit segment.

💡IPv6

IPv6, or Internet Protocol version 6, is the most recent version of the Internet Protocol. It was developed to replace IPv4 due to the exhaustion of available addresses. The script explains that IPv6 addresses are 128 bits in length, allowing for a significantly larger number of unique addresses. This is crucial as it ensures that there are enough addresses for the growing number of devices connecting to the internet. An example of an IPv6 address from the script is FE80::5D18:652:CFFD:8F52, which is much longer and more complex than IPv4 addresses.

💡IP Address

An IP address is a unique identifier assigned to devices on a network that allows them to communicate with each other. The script discusses both IPv4 and IPv6 addresses, highlighting the differences in their structure and capacity. IP addresses are essential for identifying and locating devices on the internet, and the video emphasizes the transition from the 32-bit IPv4 to the 128-bit IPv6 to accommodate the increasing number of connected devices.

💡Binary

Binary is a numeral system that represents numeric values using two symbols, typically 0 and 1. In the context of the video, binary is used to represent the bits within an IP address. The script provides an example of how an IPv4 address is represented in binary form, with each 8-bit segment (octet) being converted from binary to decimal to form the recognizable IP address structure.

💡Subnet Mask

A subnet mask is used in networking to divide a network into subnetworks, or subnets, and to identify the network and host portions of an IP address. The script explains that subnet masks are crucial for determining which part of an IP address belongs to the network and which part to the host. An example of a subnet mask provided in the script is 255.255.255.0, which is used in conjunction with an IP address to define the device's network and host identifiers.

💡Default Gateway

The default gateway is the IP address of a router or other networking device that provides a path for devices on a local network to access external networks, such as the internet. In the script, the default gateway is mentioned as a necessary configuration parameter for a device that needs to communicate outside its local subnet, with the example of 192.168.1.1 being provided.

💡DNS Server

A DNS (Domain Name System) server is a server that translates human-friendly domain names, such as www.google.com, into IP addresses that computers use to identify each other on the network. The script highlights the importance of DNS servers in facilitating the translation between domain names and IP addresses, making it easier for users to access websites without needing to remember IP addresses. The script also mentions 8.8.8.8 and 8.8.4.4 as examples of DNS servers managed by Google.

💡Domain Name

A domain name is a human-readable address that represents an IP address on the internet. It allows users to access websites without needing to remember numerical IP addresses. The video script explains that instead of typing IP addresses into a browser, users can type domain names, which are then translated to IP addresses by DNS servers.

💡Network Administrator

A network administrator is a professional responsible for managing and maintaining an organization's computer network. In the context of the video, the network administrator is typically the one who assigns IP addresses, subnet masks, and other network configurations to devices on a network. The script implies that the network administrator plays a crucial role in the setup and management of IP addressing schemes.

💡Hexadecimal

Hexadecimal is a base-16 number system used in digital and computer systems. It is often used to represent binary data in a more compact form. In the script, hexadecimal is mentioned as the format used to represent IPv6 addresses, making them more manageable to handle than their binary equivalents. The IPv6 address example in the script is expressed in hexadecimal format.

💡Router

A router is a networking device that forwards data packets between computer networks. In the video, the router is mentioned in the context of the default gateway, which is the IP address of a router that allows devices to communicate outside their local network. Routers play a critical role in directing traffic and enabling communication across different networks.

Highlights

IPv4 is the primary protocol for communication on today's networks.

IPv4 addresses are used on devices for communication.

IPv6 is a newer version of IP with broader support in major operating systems.

A device can have both IPv4 and IPv6 addresses for internet communication.

IPv4 addresses consist of four numbers separated by periods, totaling 32 bits.

IPv4 addresses can be represented in binary, with each segment being 8 bits or 1 byte.

The maximum value for each octet in an IPv4 address is 255.

IPv4 address capacity was exceeded, leading to the creation of IPv6.

IPv6 addresses are 128 bits long, allowing for a vast number of unique addresses.

IPv6 addresses can accommodate the global population with multiple addresses each.

IPv6 addresses are divided into eight groups of 16 bits each.

IPv6 addresses are typically represented in hexadecimal format.

DNS is crucial for referring to servers by name instead of complex IPv6 addresses.

IPv6 addresses are often assigned with a 64-bit subnet mask.

Assigning an IP address requires the address itself, a subnet mask, and a default gateway.

DNS servers translate domain names to IP addresses for routing purposes.

Configuring multiple DNS servers ensures redundancy in case one is unavailable.

Google manages DNS servers 8.8.8.8 and 8.8.4.4, providing reliable DNS services.

Transcripts

IP version 4, which you will commonly see written as IPv4,

is the primary protocol for almost everything

that we do on today's networks.

If you're communicating between two different devices,

IP addresses will be used on both of those devices.

There's a newer version of IP called IP version 6 or IPv6.

And you'll find that most major operating systems now

support both IPv4 and IPv6 on those systems.

These are the IP addresses on my device.

I have both IPv4 addresses and IPv6 addresses

that have been assigned to my computer.

This means that I can communicate to any other device

on the internet, either using IPv4 addresses or IPv6.

IPv4 addresses are four separate numbers,

all separated with a period.

So an example of an IPv4 address would be 192.168.1.131.

We can also view this in a binary form.

You can see there are 32 total bits in an IPv4 address.

And they're separated into these four different blocks.

This is the binary representation of 192.

This is the binary representation of 168,

and so on.

You'll sometimes hear these referred to as 8-bit segments,

one byte, or one octet.

And having four of those together

is 32 total bits or 4 bytes of an IPv4 address.

If you were to convert this binary value back to decimal,

you would see that 11000000 is 192.

This also means if we have eight of these bits

and they're all set to 1, the maximum value would be 255.

So any of these groups or octets can

have a maximum value of 255.

We quickly realized with the popularity of the internet

that we were going to exceed the capacity of what

IPv4 addresses could provide.

So we created IPv6 which was a new form of IP that

had a much larger address.

You can see that an IPv6 address is 128 bits in length.

This means that you can have a very large number

of total addresses, which ultimately means

that the $6.8 billion people on Earth

could have a very large number of addresses

for each individual person.

This gives us enough addresses to assign an IPv6 address

to almost anything that we might use.

You can see that IPv6 addresses are separated

into eight different groups.

And each one of those groups consists of 16 bits.

This is also two bytes or two octets.

Instead of displaying these addresses as binary or decimal,

you can see that in IPv6, we choose to address

these in hexadecimal format.

So a common IPv6 address might be FE80 colon colon 5D18 colon

652 colon CFFD colon 8F52.

As you can tell, it's a much larger address.

And in some ways, it's a much more difficult address

to try to memorize.

For that reason, your DNS is going

to be a very important tool to use on your network,

because you'll very often be referring to these servers

by their name instead of their very long and relatively

complicated IPv6 address.

We also tend to see IPv6 addresses assigned

with a 64-bit subnet mask.

That means that the first 64 bits are the network address,

and the last 64 bits are the host address.

If you're assigning an IP address to a device,

there are a number of important configuration parameters

you need to add.

The first would obviously be the IP address itself.

So for IPv4, you might assign it an IP address of 192.168.1.165.

Every device on your network needs a unique IP address.

So you have to make sure there are

no duplicates when you start assigning these IP

addresses to devices.

Along with the IP address, we also

need to assign a subnet mask.

This will normally be assigned by the network administrator.

And it's usually a format like this one,

such as, 255.255.255.0.

Subnet masks are used by the local device

to determine what subnet it happens to be a part of.

So it uses this to mask out the IP address, leaving only

the host address at the end.

You'll often be provided both of these values at the same time.

So if you're assigning an IP to a device,

someone may tell you to assign 192.168.1.165

with a subnet mask of 255.255.255.0.

If you only have one of these parameters,

you won't be able to complete the IP address assignment.

Both of these parameters are used in conjunction

with each other.

And you have to have both of them to assign an IP.

If the device also needs to communicate outside

of your local subnet, and most devices do,

you'll need to also assign a default gateway.

This is the IP address of a router

that allows you to communicate outside of your local subnet.

So the default gateway in this particular example

is 192.168.1.1.

In most cases, this is the bare minimum

of configurations you would need to assign to a local device.

So you would need an IP address, a subnet mask, and a default

gateway.

As I mentioned earlier, the domain name system server

or DNS server is also an important component.

We don't commonly type an IP address in the browser

that we're using.

Instead we type www.professormesser.com

or www.google.com.

It would be very complicated if we

had to remember all of these IP addresses and type them

in manually every time we wanted to visit one of these websites.

Instead, we have a service that does this for us.

It converts between these names to an IP address.

This is because the routers and other devices on our network

don't know what these names mean,

but they do know where to send your traffic if there's an IP

address associated with it.

So we need something that can translate

between the fully qualified domain

name, such as professormesser.com,

to an IP address.

And it's the DNS server that provides that translation.

We would commonly configure a DNS in the IP settings

of your operating system.

So in my particular case, I've assigned 8.8.8.8.

You'll also notice there are other DNS servers listed

on my machine.

That's because DNS is such a critical resource

that it's very common to assign two separate DNS IP addresses

to your configuration.

That way if one DNS is not available,

you have another DNS that you can use.

In my example, I have 8.8.8.8 and 8.8.4.4, both of which

are DNS servers managed by Google.